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1.
J Assist Reprod Genet ; 34(5): 659-669, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28236108

RESUMO

Complex chromosome translocations are structural chromosomal rearrangements involving three or more chromosomes and more than two breakpoints. A complex chromosome rearrangement was detected in a phenotypically normal female patient that was referred to the hospital for genetic counseling due to reproductive failure. A cytogenetic evaluation was performed, according to standard method of chromosomal analysis, using G-banding technique. The patient's karyotype showed a balanced complex chromosome rearrangement (BCCR) involving chromosomes 1, 8, and 11 with three breakpoints 1p31, 8q13, and 11q23. The karyotype designed according to ISCN (2013), is 46,XX,t(1;8;11)(p31;q13;q23) (8qter→8q13::1p31→1qter;8pter→8q13::11q23→11qter;11pter→11q23::1p31→1pter). Additionally, the proband's mother and brother were tested, resulting in the same exact translocation. In this study, we describe all possible meiotic segregations regarding this translocation, as well as the clinical phenotypes which could arise, if unbalanced products of conception survive. This is a rare case of familial complex chromosome rearrangement, giving a view for its reproductive consequences.


Assuntos
Aberrações Cromossômicas , Reprodução/genética , Translocação Genética/genética , Bandeamento Cromossômico , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 8/genética , Análise Citogenética/métodos , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Cariotipagem , Masculino , Linhagem
2.
Hum Reprod ; 29(8): 1603-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25006203

RESUMO

STUDY QUESTION: How has the interface between genetics and assisted reproduction technology (ART) evolved since 2005? SUMMARY ANSWER: The interface between ART and genetics has become more entwined as we increase our understanding about the genetics of infertility and we are able to perform more comprehensive genetic testing. WHAT IS KNOWN ALREADY: In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and ART and published an extended background paper, recommendations and two Editorials. STUDY DESIGN, SIZE, DURATION: An interdisciplinary workshop was held, involving representatives of both professional societies and experts from the European Union Eurogentest2 Coordination Action Project. PARTICIPANTS/MATERIALS, SETTING, METHODS: In March 2012, a group of experts from the European Society of Human Genetics, the European Society of Human Reproduction and Embryology and the EuroGentest2 Coordination Action Project met to discuss developments at the interface between clinical genetics and ART. MAIN RESULTS AND THE ROLE OF CHANCE: As more genetic causes of reproductive failure are now recognized and an increasing number of patients undergo testing of their genome prior to conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and PGD may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from RCTs to substantiate that the technique is both effective and efficient. Whole genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. LIMITATIONS, REASONS FOR CAUTION: The legal landscape regarding assisted reproduction is evolving, but still remains very heterogeneous and often contradictory. The lack of legal harmonization and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe, and beyond. WIDER IMPLICATIONS OF THE FINDINGS: This continually evolving field requires communication between the clinical genetics and IVF teams and patients to ensure that they are fully informed and can make well-considered choices. STUDY FUNDING/COMPETING INTERESTS: Funding was received from ESHRE, ESHG and EuroGentest2 European Union Coordination Action project (FP7 - HEALTH-F4-2010-26146) to support attendance at this meeting.


Assuntos
Técnicas de Reprodução Assistida/tendências , Acreditação , Células-Tronco Embrionárias , Epigenômica , Europa (Continente) , Feminino , Genética Médica/ética , Genética Médica/legislação & jurisprudência , Genética Médica/tendências , Instabilidade Genômica , Acessibilidade aos Serviços de Saúde , Humanos , Infertilidade Feminina/genética , Infertilidade Masculina/genética , Masculino , Turismo Médico/tendências , Diagnóstico Pré-Implantação/ética , Diagnóstico Pré-Implantação/tendências , Medicina Reprodutiva/ética , Medicina Reprodutiva/legislação & jurisprudência , Medicina Reprodutiva/tendências , Técnicas de Reprodução Assistida/efeitos adversos , Técnicas de Reprodução Assistida/ética , Técnicas de Reprodução Assistida/legislação & jurisprudência , Sociedades Médicas
3.
F S Rep ; 5(2): 145-151, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38983741

RESUMO

Objective: To study the possibility of increasing the cooling rates of the vitrification procedure in a closed system with the use of aluminum oxide as an intermediate coolant. Design: Case report. Subjects: Six patients undergoing procedures for assisted reproduction. Intervention: Comparative studies of cryopreservation of donor embryos with aluminum oxide as an intermediate cooling agent (experimental group) and without it (control group) have been performed. After thawing, the embryo morphology and its potential to develop to the blastocyst stage have been assessed. The methodology was then applied to clinical practice. Main Outcome Measures: Twenty embryos of 6 patients have been vitrified on day 4 after fertilization with the use of aluminum oxide as an intermediate coolant. Fourteen of them have been thawed. All have displayed normal morphology and 10 have formed blastocysts after 24 hours of culture. Four of the patients received embryo transfer with 2 embryos and the other 2 with single embryos. Results: After preliminary comparative studies of embryos frozen with aluminum oxide and a control group, the results showed no statistically significant difference between their quality and potential to reach to blastocyst stage. That gave us ground to apply the methodology in clinical practice. After the embryo transfer, 3 clinical pregnancies with successful live births have been obtained. Conclusions: Our experience shows that preimplantation embryos can be cryopreserved aseptically, in closed systems, with the help of aluminum oxide as an intermediate coolant.

4.
Life (Basel) ; 12(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36362995

RESUMO

The aim of our study was to determine the type and frequency of chromosomal aberrations and polymorphisms in men with different degrees of spermatogenic failure in comparison to men with normozoospermia, in order to find correlations between cytogenetic findings and the abnormal results of semen analysis. In our study, we performed cytogenetic analysis in 901 infertile men, divided into five groups according to semen analysis-normozoospermia (86), asthenozoospermia (394), oligoasthenozoospermia (182), severe male factor (100), and azoospermia (139). The frequency of polymorphisms was similar in all groups (11-16%, without significant differences). The frequency of numerical and structural aberrations increases with the degree of the spermatogenic failure (3.5% in normozoospermia, 5.6% in asthenozoospermia, 9.8% in oligoasthenozoospermia, 9% in severe male factor, and 13.5% in azoospermia). We found a significantly higher incidence of numerical chromosomal aberrations in severe male factor (7%) and azoospermia (9.3%). Oligoasthenozoospermia occured in 45% of cases with translocation, compared to 20% in the group with a normal karyotype. We revealed that chromosomal translocations are tightly associated with oligoasthenozoospermia, whereas numerical chromosomal aberrations-with severe male factor and azoospermia. The impact of chromosome polymorphisms on male infertility should be studied in greater detail.

5.
Taiwan J Obstet Gynecol ; 59(1): 99-104, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32039809

RESUMO

OBJECTIVE: To study two major molecular alterations in spontaneous abortions (SA) with unexplained etiology - fetal genomic anomalies and the endometrial expression of main angiogenic factors VEGFA/VEGFR2 and chemokines SDF-1/CXCR4. MATERIALS AND METHODS: Whole genome copy number analysis by arrayCGH or Next Generation Sequencing (NGS) was applied for detection of fetal genomic imbalances. The abortive decidua of SA without fetal aneuploidies was further investigated for expression levels of the abovementioned factors using real time PCR analysis. A total of 30 abortive materials were collected from spontaneous abortions after exclusion of known predisposing factors. RESULTS: In 21 of 30 spontaneous abortions (70%), genomic anomalies were discovered by whole genome copy number analysis. Numerical anomalies were detected in 90% of aberrant cases, and in 10% - structural aberrations were revealed. An increased expression for essential factors of angiogenesis was identified in spontaneous abortions' tissues - 3.44 times for VEGFA and 10.29 times for VEGFR2. We found an average of 14 times increase in the expression levels of SDF-1 and 3.21 times for its receptor CXCR4. CONCLUSION: We could suggest the occurrence of increased angiogenesis in SA without fetal aneuploidies, compared to the control tissues, which could lead to increased oxidative stress and fetal loss.


Assuntos
Aborto Espontâneo/genética , Indutores da Angiogênese/metabolismo , Feto/irrigação sanguínea , Adulto , Aneuploidia , Quimiocina CXCL12/metabolismo , Aberrações Cromossômicas/embriologia , Variações do Número de Cópias de DNA , Decídua/metabolismo , Feminino , Morte Fetal/etiologia , Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neovascularização Patológica/genética , Estresse Oxidativo/genética , Gravidez , Receptores CXCR4/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
6.
ScientificWorldJournal ; 6: 686-90, 2006 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-16799739

RESUMO

The implementation of safe and maximally effective ovarian stimulation is a major aim for in vitro fertilization (IVF) teams. The goal of controlled ovarian hyperstimulation (COH) is to supply enough oocytes with normal maturation to insure the consequent biological procedures. A variety of different stimulation protocols have been suggested and an individual selection of the correct stimulation protocol is mandatory. The aim of the present study is to evaluate the correlation between number of retrieved oocytes and clinical pregnancy rate (CPR) after IVF or intracytoplasmic sperm injection (ICSI) procedures. We reviewed 1017 cycles in a total of 975 patients. The study results clearly demonstrate that the aspiration of less than 5 oocytes significantly reduced pregnancy rate. The aspiration of a large number of oocytes (>15) does not lead to an increase of the treatment effect and, at the same time, increases the risk of ovarian hyperstimulation syndrome. The major goal is to obtain 5-15 oocytes as a "gold standard", connected to optimal pregnancy rate after assisted reproduction (ART).


Assuntos
Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Humanos , Oócitos , Indução da Ovulação/estatística & dados numéricos , Gravidez , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos
7.
JBRA Assist Reprod ; 20(3): 142-9, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27584608

RESUMO

The aim of this overview is to discuss the current information about the search for the optimum yield of gametes in assisted reproduction, as one of the major pillars of IVF success. The first topic is focused on the number of male gametes and the possible impact of some genetic traits on these parameters. The number of spermatozoa did not seem to be crucial when there is no severe male factor of infertility. Genetic testing prior to using those sperm cells is very important. Different methods were applied in order to elect the "best" spermatozoa according to specific indications. The next problem discussed is the importance of the number of oocytes collected. Several studies have agreed that "15 oocytes is the perfect number," as the number of mature oocytes is more important. However, if elective single embryo transfer is performed, the optimal number of oocytes will enable a proper embryo selection. The third problem discussed concerns fertility preservation. Many educational programs promote and encourage procreation at maternal ages between 20-35 years, since assisted reproduction is unable to fully overcome the effects of female aging and fertility loss after that age. It is also strongly recommended to ensure a reasonable number of cryopreserved mature oocytes, preferably in younger ages (<35), for which an average of two stimulation cycles are likely required. For embryo cryopreservation, the "freeze all" strategy suggests the vitrification of good embryos, therefore quality is prior to number and patient recruitment for this strategy should be performed cautiously.


Assuntos
Embrião de Mamíferos , Oócitos , Técnicas de Reprodução Assistida , Espermatozoides , Feminino , Preservação da Fertilidade , Humanos , Masculino , Oócitos/citologia , Oócitos/fisiologia , Espermatozoides/citologia , Espermatozoides/fisiologia
8.
Biomed Res Int ; 2014: 306505, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24783200

RESUMO

The current morphologically based selection of human embryos for transfer cannot detect chromosome aneuploidies. So far, only biopsy techniques have been able to screen for chromosomal aneuploidies in the in vitro fertilization (IVF) embryos. Preimplantation genetic diagnosis (PGD) or screening (PGS) involves the biopsy of oocyte polar bodies or embryonic cells and has become a routine clinical procedure in many IVF clinics worldwide, including recent development of comprehensive chromosome screening of all 23 pairs of chromosomes by microarrays for aneuploidy screening. The routine preimplantation and prenatal genetic diagnosis (PND) require testing in an aggressive manner. These procedures may be invasive to the growing embryo and fetus and potentially could compromise the clinical outcome. Therefore the aim of this review is to summarize not only the new knowledge on preimplantation and prenatal genetic diagnosis in humans, but also on the development of potential noninvasive embryo and fetal testing that might play an important role in the future.


Assuntos
Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Previsões , Testes Genéticos/tendências , Resultado da Gravidez/genética , Diagnóstico Pré-Implantação/tendências , Diagnóstico Pré-Natal/tendências , Feminino , Humanos , Recém-Nascido , Gravidez
9.
Eur J Obstet Gynecol Reprod Biol ; 169(2): 261-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23664380

RESUMO

BACKGROUND: Preimplantation genetic diagnosis (PGD) is a widely used technique for couples at genetic risk and involves the diagnosis and transfer of unaffected embryos generated through in vitro fertilization (IVF) techniques. STUDY DESIGN: For those couples who are at risk of transmitting a genetic disease to their offspring, preimplantation embryos can be selected according to their genetic status as well as human leukocyte antigen (HLA) compatibility with the affected child. Stem cells from the resulting baby's umbilical cord blood can be used for transplantation to the affected sibling without graft rejection. RESULTS: Here we report successful hematopoietic stem cell transplantation (HSCT) after the birth of a healthy infant, who was born after successful PGD testing with both cleavage stage and blastocyst stage biopsy for the purpose of diagnosis of ß-thalassemia and HLA compatibility. CONCLUSION: The specific feature of this work is not only to have the first successful HSCT achieved in Bulgaria after using preimplantation HLA typing technique, it also demonstrates how to accomplish this success via cross-border collaboration of different units, which makes the application of these sophisticated methods possible in hospitals not having the necessary equipments and expertise.


Assuntos
Antígenos HLA/genética , Transplante de Células-Tronco Hematopoéticas , Diagnóstico Pré-Implantação , Talassemia beta/terapia , Adulto , Amniocentese , Biópsia , Feminino , Técnicas de Genotipagem , Humanos , Nascido Vivo , Masculino , Gravidez , Talassemia beta/diagnóstico , Talassemia beta/imunologia
10.
Eur J Hum Genet ; 21 Suppl 2: S1-21, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24225486

RESUMO

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation - ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005.


Assuntos
Reprodução/genética , Técnicas de Reprodução Assistida , Animais , Anormalidades Congênitas/epidemiologia , Modelos Animais de Doenças , Células-Tronco Embrionárias , Epigênese Genética , Europa (Continente) , Feminino , Fertilização in vitro/métodos , Aconselhamento Genético , Testes Genéticos , Variação Genética , Genética Médica , Guias como Assunto , Humanos , Infertilidade/genética , Infertilidade/terapia , Masculino , Turismo Médico , Políticas , Gravidez , Diagnóstico Pré-Implantação , Medicina Regenerativa , Técnicas de Reprodução Assistida/efeitos adversos , Técnicas de Reprodução Assistida/ética , Técnicas de Reprodução Assistida/legislação & jurisprudência , Técnicas de Reprodução Assistida/tendências , Sociedades Científicas
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